Tacker and stabilizer therefor



Feb. 15,1944. I A, BY I 2,341,530v

TACKER AND STABILIZER THEREFOR Filed Feb. 17, 1940 I 3 Sheets-Sheet l ATTORNEY Feb. 15, 1944. v A CR OSB 1 2,341,530

TACKER AND STABILIZ ER THEREFOR Filed Feb. 17, 1940 3 Sheets-Sheet 2 ATTGRNEY Feb. 15, 1944. A. RosBY 2,341,530

- TACKER-AND STABILIZER THEREFOR File d Feb'. 17, 1940 s Sheets-Sheet 5 I87 /86 we 75 I alNVENTOR 4 v .Q @447 ATTORNEY Patented. Feb. 1944 UNITED STATES I PATENT OFFICE TACKER AND STABEIZER. THEREFOR Stephen A. Crosby, Chicago, Ill. Application February 17, 1940, Serial No. 319,380 v 11 c n... (on. 1-49) The invention relates to a functionally and structurally improved stapling machine and more particularly to a staple tacker. In staple tacking machines of the prior art, the driving impact imparted by thedriver usually created an undesirable rebounding or recoiling action thus appreciably and disadvantageously reducing the ultimate effect of the desired blow or force against the driven staple. It is thus an important object of the present invention to materially overcome this disadvantage in positioning a concentrated laminated mass over the driver to absorb the recoil of the frame of the tacker and thereby effectively reduce undesirable rebounding of the frame at the instant of impact of the driven staple against material into which it is driven, thus resulting in administering a relatively hard blow to the staple in more efiectively driving the staple to its desired tacking relation. The invention has as other salient objects to'provide a tacker. that is convenient to load; that is convenient to carry about from place to place; that is of relatively light weight, thus reducing fatigue of the operator; that is smooth in exterior contour, hence preventing tearing or catching of the lining of a pocket of the clothing of the operator; that is relatively narrow in widthto allow close positioning of the frame of the tacker adjacent to vertical walls or floor moulding and into corners defined by the latter; that has service able means to permit opening 'of the rame by a single band of the operator; that has power means to provide instantaneous impact on the part of the driver or ram'against the .staple and shock absorbing means toallow gradual deacceleration of the driver; that has localized stabilizing means of relatively greater mass than the driver, and is sustained by the frame which is hollow and of relatively light sheet metal material which is merely skin stressed during tacking operations; and that has target or indicator means to determine the exhaustion of staples within the niagazine even though the latter be closed. Further objects, advantages, and functional and structural features of the invention deal with: the provision of means to permit convenient withdrawal of the staple driving blade of the reciprocable driver from the staple raceway or guideway upon lifting of the pivoted cover of the tacker from the staple magazine thereof without accidentally lifting the front portion of the staple strip from the magazine, hence preventing accidental spillage of staples out of the magazine in instances where it is desired to open the latter for inspection or loading; and the provision of novel shiftable supporting means to prevent transverse rocking of the tacker when utilized adjacent the vertical walls or mouldin of a room or chamber. Other important objects pressed position, and the actuating handle therefor in a normally raised relation.

Figure 4 is a fragmentary view of Fig. 3 however showing the driver approaching its fully raised position.

Fig. 5 is a view similar to Fig. 4 showing the driver free of the trip pawl and the plunger thereof moving downwardly towards the fixed abutment or anvil.

Fig. 5 is a fragmentary sectional view of the pivoted cover illustrating the driver depressed and the control handle returning to its normally raised position.

Fig. 5 is a fragmentary sectional view of the cover showing the driver leaving the plunger head when the ejecting blade is driving a staple into relatively soft or flufiy material.

Fig. 6 is a sectional view on the line 6-4: of Fig. 3.

Fig. 7 is a sectional view on the line 7-1 of Fig. 3.

Fig. 8 is a sectional view on the line 8-8 of Fig. 3.

Fig. 9 is a transverse sectional view on the line 9-9 of Fig. 3.

Fig. 10 is a fragmentary perspective view of the tacker.

Fig. 10 is an underneath view of the front part of the magazine.

Fig. '11 is a fragmentary perspective view of the tacker shown partly turned over.

Fig. 11 is a perspective view of the magazine.

Fig. 12 is a perspective view of the shock absorbing laminated head to reduce recoil of the tacker.

Fig. l2 is a fragmentary perspective view of the case of the tacker.

Fig. 13 is a fragmentary sectional view of the tacker showing the cover and the magazine in a fully opened relation.

' Fig. 14 is a perspective view of the locking retainer for the slidable saddle.

Fig. 15 is a sectional view on the line I--|5 of Fi 3.

Fig. 16 is a sectional view on the line I 6-l8 of Fig. 3.

Fig. 17 is a fragmentary view of the tacker showing the latch depressed for unlocking the magazine to permit Opening of the pivoted cover.

Fig. 18. is a perspective view of the driver.

Fig. 19 is a sectional view on the line l9-i9 of Fig. 6.

Fig. 20 is a perspective view of the latch or trigger, and

Fig. 2-1 is a fragmentary view of the control arm.

Illustrative of the embodiment disclosed, the tacker T comprises, a magazine ill and the pivoted cover II. The magazine is of sheet metal and includes a bottom wall [2, side walls l3, and the front transverse wall l4.

Fixedly sustained within the magazine is the inverted U-shaped rail l5 having a top wall l6 (Fig. 7) disposed below the elevation of the top faces I! of the magazine sides l3. Depending from the top wall l6 of the rail are the legs or sides l8 which are spaced from side walls l3 of the magazine and define longitudinal gaps IQ for slidably guiding legs 20 of the staples 2! of the staple strip 22 having their crown portions 23 slidably seated on the top wall I6 of the rail.

The inverted U-shaped metal staple follower 24 is slidably guided on the fixed rail and is provided with depending legs 25 (Figs. 2 and 8) having inwardly turned lugs 26 (Figs. 5 and 8) mov ably disposed in gaps 21 between the sides l8 of the rail and the bottom wall l2 of the magazine.

, Thus although the follower 24 is slidably guided .in the magazine, it is interlocked with the rail.

The forward transverse face 28 (Fig. 4) of the rail I5 is spaced from the inner transverse inner face 29 of the front wall l4 of the magazine thus defining a vertical staple guideway 30. Each side l8 of the rail has at its forward ends spaced depending lugs 3| and 32.

Lugs 3| closely straddle the sides of the square shaped lip 33 of the bottom wall l2 of the magazine and are disposed in the notches 34 and are spaced from inner faces 35 of the sides l3 of the magazine to provide clearing passages 38 for staple chips to permit the latter to fall out of the magazine to prevent clogging. Rear lugs 32 are approximately received and anchored in the locating openings 31 in the bottom wall of the magazine.

It should be understood of course that the rear part of the rail is fixed and suspended within the, magazine to sustain the bottom faces 31 (Fig. 5) of the sides of the rail the required distance away from the bottom wall l2 of the magazine to provide gaps 21 to permit free sliding of the lugs 26 of the follower 24 which has'a reduced front portion 38 having the front end face 39 adapted to be disposed in alinement with the front transverse face 28 of the rail when shoulders 40 of the follower strike the shoulders 4| defined by the lugs 32. In this way the reduced part 38 of the follower is prevented from projecting into the staple guideway 30 even at times when the latter is exhausted of staples.

Specifically however the rear part of the rail includes a lip 42 (Fig. 13) fixedly positioned in slot 43 in the rear transverse wall 44' of the magazine for sustaining the sides of the rear part of the rail in spaced relation to the inner faces of the sides and the bottom inside face of the magazine and extending rearwardly of wall 44' are the spaced outside ears 44 (Figs. 1, 9 and 13) of the sides l3 of the magazine. These ears are provided with alined openings or bearings 46 to slidably guide the elongated fulcrum pin 45 transversely of the magazine. These ears 44 also straddle the spaced ears or lugs 41 depending from the sides 48 of the hollow sheet metal case 49 of the cover of the tacker. By this arrangement the case is rotatably or pivotally guided on the fulcrum pin 45 by the outside cars 44 and of course against transverse displacement relative to the magazine, that is, case 49 has its lugs 41 and particularly bearings or guide openlugs 50 (Fig. 9) thereof rotatably mounted on the elongated shiftable fulcrum pin 45 having its reduced ends 5| secured to the upstanding sides '52 of the one piece saddle or yoke 53 which has a seat 54 movable transversely of the magazine in the alined gaps or cut outs 55 (Fig. 13) in the sides l3. It will be observed that the bottomface of seat 54 is'in alinement with the lower face of the bottom wall l2 of the magazine and in fact constitutes a relatively elongated supporting face to prevent transverse tilting or rocking of the ient, flexible and relatively thin sheet metal spring clip or loop denoted 55 (Figs. 9, 13 and 14) is utilized. This clip or retainer comprises hingedly merged curved jaws 51 and 58 defining the gap 59 and common to these jaws and integral therewith is the loop 60. The curved jaws are provided with the locking and alined inwardly projecting detents 6| which snap into gap 62 of the reduced portion 63 of the fulcrum pin 45.. This gap 62 is centrally located on the fulcrum pin 45 and-its side walls disengageably interloc}: with or embrace the alined detents when the saddle 53 is slidably shiftedtransversely of the magazine to its neutral position in which instance sides 52 of the saddle are widely spaced from the sides of the magazine in which case justing the saddle to meet the convenience of the operator. For example, in Figs. l and 2, the saddle is in its neutral and locked position and may be readily shifted to appreciably extend beyond the left hand side or to the right hand side of the magazine. For purposes of illustration, the saddle is shownin Fig. 9 appreciably extending beyond the left hand side of the magazine and in the dash and dotted lines as extending appreciably beyond the right side'o'f the magazine. In either extreme position of the saddle slidable fulcrum pin 45 is freely encompassed by the spaced jaws 51 and 58. In the full line position of the saddle in Fig. 9 the right hand side of the tacker may be placed near a wall or'may be placed in corners to get close to the moulding and thus the-left part serves as a balancer or stabilize support to prevent rocking of the tacker when confined in close quarters. Of course the saddle may be reciprocably adjusted to get close to walls or close to corners at either side of the tacker and linear displacement of the saddle is limited by the outside ears 44 cooperating with the side 82.

Pursuant to desired use of the tacker when the saddle has been shifted to either side thereof to facilitate balancing. the saddle may be quickly reset in its neutral position by shifting the same in the desired direction whereby the fulcrum pin is slidably guided by the alined bores of the cars 64 and 41 until the locking detents 6| snap into or enter gap 62 about the reduced part 88 of the fulcrum pin. To. unloclc'the retainer from the fulcrum pin, one side as 52 of the saddle is manually forced towards thetacker in which event a side wall of the gap 62 shifts the resilient and separable deteuts out of gap 82, thus causing at this time the jaws or lips 51 and 58 in: blade 98 provided with corner tapered projections 9| (Fig. 18). It should be observed that where the case 49 and sheath I8 are in proper assembled relation the vertical transverse faces 92 (Figs. 4 and 5) of the spaced extensions 93 of n'ated core and these guide faces 98 are positioned in alinement with the spaced bearing faces 88 of I the case 49 by the locating lugs 84 and notches to be slightly separated but their inherent resiliency or flexibility by reason of the loop restores them to their normal slightly spaced relation when the saddle has been shifted to its neutral position in whichcase the jaws automatically retractthe detents 9| and are interlocked with the side walls of'gaps 92.

By the present arrangement the cover C for the magazine is pivotally mounted andconsequently the cover may be reciprocably rotated and of course rearwardly relatively to the case until lower margin'85 of the curved top or closure wall 66 of the case 49 of the cover abuts the stop flange 61 (Fig. 13) extending from the base orseat 54 of the reciprocable saddle 58 in which event the cover is approximately one hundred and twenty degrees away from the magazine. Hence the latter at this time is fully opened and complete access is had to. the rail and of course to the staple guideway 38.

The cover C embodies the hollow sheet metal case 89 and the U-shaped hollow sheath I8.pro-

vided with the front transverse wall II having Since the stabilizing core It is utilized to re- I tain and house the upper end of the power spring 88, the outer laminations I5 have their arms 8I extending below the arms 82 of the intermediate laminations I6 which are suitably notched to provide the recess 83 in which the upper part .of the power spring 88 is located and retained.

The outer plates I5 of the stabilized core I4 have depending lugs 84 fitting into the locating notches 85 in the front portions I3 of the sides 48 of the case 49. core is positively positioned in respect to or interlocked with the case 49. The core is also pivotally located in respect to the sheath 18 by reason of the forwardly projecting and alined lugs 86 of the intermediate laminations I6 which lugs extend into the positioning slot 81 (Fig. 2) in front transverse wall II of the sheath.

In the assembled relation of the case and sheath, the transverse end faces 98 (Figs. 12 and of the front parts I3 of the sides 48 of the case constitute the rear bearing surfaces for the reciprocable and rectangularly shaped staple driver or ram 89 comprising the steel staple eject- By this arrangement, the" 95. In fact, faces 88 and 98 constitute the vertically alined rear bearing faces of the driver guide bore or socket generally denoted 91 (Fig. 15) characterized also by the inner faces 98 of the sides 12 of the sheath and the transverse inner surface 94 of the front wall 1 I Fixedly anchored to the reclprocable hollow driver 89 is the bar I88 which interrupts the elongated bore or well I8! therein. The bottom wall I82 (Figs. 5 and 18) of the driver is provided with an opening I83 for slidably guiding shank I84 of the plunger I85 having the enlarged head I88 normally retained against the seat or bottom wall I82 by the helicoidal normally expanded shock absorbing spring IIlI- having its lower and continuously abutting the head of the plunger and its upper end abutting the anchored plate I88 which in fact forms a seat for the lower end of the normally expanded helicoidal power accelerating spring 88 disposed in vertical alinement with the shock absorbing spring IIlIwhich is appreciably greater in stiffness than the power or accelerating spring 98. In other words, where a unit load is applied to each of these springs, the deaccelerating spring I87 will have an appreciable less linear deflection than the power spring 88 or more specifically stated, the momentum produced in the driver by the .power' spring to effect a linear deflection thereof of three quarters of an inch is negatived by the shock absorbing spring in undergoing a linear deflection to the extent of one sixteenth of an inch where the driver is idly operated, without any staples or in instances where a staple is driven out of the tacker by the blade into the material and body for example, cardboard and wood or flufiy objects to be tacked together, in such instances while the power spring deflects substantially to the order of three quarters of an inch, the shock absorbing spring undergoes a linear deflection of a few thousandths of an inch only for the material into which the staple is driven absorbs most of the momentum imparted to the driver by the power accelerating spring.

Positioned below the spring controlled plunger I85 and cooperating therewith is the metal anvil or abutment block II8 whichclosely fits into the the anvil H8 .is interlocked with the case and thus is held against transverse movement rela tive to the sheath.

Spaced ears II5 (Figs. 1 and 2) extending from sides I2 of sheath I8 closely straddle and em- 78 brace the spaced forward portions I3 of the sides 48 of the case and a rivet or fulcrum pin I I6 holds ears II5 against the outer faces of the portions 13, the fulcrum pin II6 however pivotally supports and passes through the forwardly projecting and spaced arms 1 of the control level or handle generally denoted II8 having its manip ulating portion II9 xtending rearwardly of the sheath.

Associated with the control handle H8 is thepivoted pawl or plunger actuator I20 having a front wall or lip I2I from which rearwardly extends the spaced sides I22 pivoted on fulcrum pin wise direction or towards the plunger which in-- cludes the reentrant notch I30 for receiving lip I2I and the shoulder I3I adapted to be actuated by lip I2I of the rockable pawl when the manipulating arm H9 is depressed against the resistance of the winged spring I32 having its coiled part I33 surrounding fulcrum rivet H6 and one wing I34 thereof abutting and confined in the arched manipulating arm I I9 while its lower wing :35 (Figs. 8 and is confined within the case More particularly however the lower wing I35 of spring I32 which normally holds the control lever elevated is retained against one of the curved lugs or humps I36 struck out of the pair of juxtapositioned reinforcing inserts I31, (Fig. 8), that is, inserts I31 have their collars I38 corresponding in shape to the elongated openings I39 in the spaced sides 48 of the case 49 and the vertical flanges or rims I40 extending outwardly of the collars straddle the spaced sides 40 and are secured thereto by the rivets I which extend transversely of the case and hold meeting faces I42 of the collars I38 together. These inserts not only reinforce the case but enhance the appearance thereof and through rivets I4I they are firmly secured to the case of the machine. Humps I36 are utilized in association with flanges I40 to locate and position the respective inserts in the sides of the case which in fact is a hollow and smooth handle reinforced by the inserts, likewise of smooth contour.

According to the invention the pivoted cover I C is automatically locked when moved to its fully closed relation with the magazine. For thisvpurpose, a swingable latch or trigger generally designated I45 is utilized. This latch is in the form of a bell crank lever comprising the spaced depending arms I46 and the rearwardly extending manipulating part I41 projecting into opening I48 in the aligned insert I31.

The spaced elbows I49 of the latch I45 are rotatably or pivotally mounted on the fixed fulcrum pin I50 carried by spaced portions 13 of the sides 48 of the case 49. The spaced depending arms I46 of the latch carry the fixed pin I5I on which wheel bearing I52 is freely rotatably mounted and about which the looped end I63 of a normally contracted helicoidal spring I64 is trained. The lower leg or reach I66 of this spring is provided with an eye I56 through which the arched retaining lug I51 of the follower is threaded and retained. -In this way the lower end of the spring is operatively connected to the staple follower block 24. I

The upper leg I58 (Figs. 3, 8 and 13) of the looped spring I54 extends rearwardly between the lower parts of the sides 48 of the swingable cover and has an eye I59 connected to hook I60 fastened to one of the sides 48. The spring I54 has several important functions, one being it normally urges to swing latch I45 counterclockwise to its locking or fully retracted position at which time if the cover be closed; overhanging terminals I'6I of pin I5I, although movably guided in arcuate slots I52 in the spaced portions 13 of the spaced sides 48 and in theregistering curved slots I53 in the spaced sides 12 of the sheath, disengageably snap into the aligned but spaced notches I62 in the wings I63 projecting upwardly from the sides I3 of the' magazine. Hence in the closed position of the cover terminals I6I which overhang or extend beyond arms I46 interlock with the wings and hold the cover closed.

In the closed relation of the cover and magazine the lower marginal portions I64 (Figs. 3 and 8) of the spaced sides 48 are telescopically received between the sides I3 of the magazine and the wings I63 which extend appreciably above the sides 48 when the cover is closed while the front lower marginal portion I65 of sides 48 of the case extend slightly although telescopically between the sides I-3 at the front part of the magazine.

Or stated in another way, marginal portions I65 of the front extension 93 (Fig. '1) of the sides 48 of the case 49 project below the bottom faces I66 of the sides 12 of the sheath 10. Thus in the closed relation of the cover, marginal portions I65 are closely straddled by sides I3 of the magazine or are telescoped in the latter. Marginal portions I64 and I65 thus properly aline the cover relative to-the magazine.

With the cover closed marginal portions I65 and the marginal portions I64 prevent upward displacement of the staples, facilitating proper sliding thereof towards the raceway 30 and it should be observed that the topfaces I1 of the sides I3 of the magazine constitute stop means to limit the extent of the telescopic projection of the case 49 into the magazine when of course the bottom faces I66 of the sheath strikes and becomes seated on the top faces I1 of the magazine.

Referring again to the normally contracted helicoidal spring I54, the lower leg I55 thereof also serves to propel or shift the slidable follower 24 (Fig. 2) away from the raceway 30 when the cover C is swung open. Thus access may be had to the rail for supplying the latter with staples. However in the closedrelation of the cover the tension imparted by the leg or reach I55 urges the follower forwardly to project the foremost staple of the staple strip into the raceway 30 and under the staple ejecting blade 90.

Briefly recapitulating, it is apparent that the looped spring I54 has at least three important functions; one, it causes terminals I6l of the roller supporting pin I5I to automatically interlock with the wings of the magazine when the cover is completely closed, and thus the cover is held against accidental opening; two, it serves to rearwardly displace the reciprocable follower on the rail when the cover is opened after the paced lugs 82 in which instant of course the I magazine is exhausted of staples.

However provision has been made to indicate I the approximate or complete exhaust of staples even though the cover beheld closed. In this connection, a target or indicator I'III (Fig. 2) has been provided. This target is in the form of a color spot, for example, red, and is painted on one of the side walls of the follower 24. In use, as the target intermittently moves automatically towards raceway 30, during the exhaust of the staples, it will ultimately register with sight opening or perforation I'll in an adjacent side wall of the magazine. This teaches the operatorthat at least one more staple remains in the magazine and of course the target may be so adjusted as to register thecomplete exhaust of the staples.

Although marginal portions I64 and IE5 of the sides of the case 69 telescope and interlock with the magazine as herein set forth, further means has been provided to supplement the proper positioning of the cover C when the latter is closed.

. To this end the transverse front wall H of the sheath i 0 embodies the depending square shaped tongue I12 fitting closely but removably into a correspondingly shaped notch I13 in the front wall Id of the magazine. with the cover closed the front walls of the sheath and magazine are therefore properly located and held in true vertical and lengthwise alignment as desired.

When the cover is closed, itwill be observed (Fig. 3) that'the staple strip 22 is urged by the lower leg 055 of spring I54 against the reciprocable staple ejecting blade 90 which-in fact closes the raceway 80 in the normal raised position of the handle H8. Thus there is a very slight yieldable frictional engagement of the foremost staple of the staple strip against the back of blade 90. It has been discovered that where it is desired to open the cover pursuant to unlocking latch I45 from the magazine, the blade acts to lift or spill the front part of the staple strip out of the magazine. With the present invention, spillage of staples out of the magazine is prevented by transverse bridge I'IS interconnecting and fixedly anchoredto the sides I3 at the front part of the magazine. This bridge it has been found resists the front part of the staple strip 22 from tilting out of the magazine when the cover is swung open. The bridge I15 also prevents transverse buckling of the sides of the magazine and constitutes means to properlyfacilitate positioning and locating of the cover relative to the magazine for the spaced walls I'lIi (Figs. 3, 11 and 11 of the spaced notches Ill in the marginal portions I65 of the case as closely but removably straddle the long sides of bridge I15 to interlock therewith. In the closed relation of the cover 0 and the magazine except for the end faces I18 of this bridge the latter is completely concealed and housed by notches II'I.

With the sheath I0 mounted on the case t0 and carrying the laminated shock absorbing and the laminated core 14 to hold the latter together while rivet I 8| holds the lower parts of the sides I2 of the sheath against the extensions 03 of the case '49, the rivet I8I' carrying the spacing sleevel82 to prevent buckling or spreading of the sides 48 of the case.

Coming now to the operation of the tacker, the metal frame thereof comprising the magazine, and cover thereof is normally closed. In such relation the handle I I8 is in its fully raised position and sides I85 of the hand guard I00 (Fig. 3) are spaced from the rear stop faces I81 of the laminated core I4 and in the fully raised position of the control handle lip I81 thereof is against the stop face I81, although it should be noted that the arms I II of the control handle IIS straddling the sides I85 of the guard are held thereto by rivet pin I88.

Although the control handle I I8 is in its normallyraised position, the driver or ram 80 is retracted as shown in Fig. 3, and lip I2I of the pivoted pawl or control actuator I20 is projecting into recess I30 under the shoulder I3I. The power spring 00 is in alignment with the shock absorbing stiff spring I01 and shank I04 of the plunger I 05 is held against the metal anvil H0 retained by sheath I0. The latch or trigger I45 is also in its normal position in which instant terminals IISI of the locking pin I5I are interlocked in the notches I62 of the wings I50 of the magazine and the reciprocable follower 26 is yieldingly urging the staple strip 22 against the back face of the ejector blade 00 of the ram or driver 89.

If the control handle II8 be depressed, lip IZI abuts shoulder ISI and the driver is slidably raised. Under these circumstances, the blade 00 moves out of the raceway 30 and the normally expanded power spring 80 is compressed.

Thereafter the follower shifts the staple strip strikes the locked abutment or anvil (Fig. 5) H0.

Although the pawl has tripped the driver it still is moving upwardly until arms H! of the control handle meet the inclined stop faces I of the laminated core (Fig. 5). The power accelerator spring 80 discharges its energy and causes the driver to be automatically retracted or returned and hence the blade drives the foremost staple of the staple. strip out of the guideway 30 and into the material to be tacked at .the

instant the crown of the driven staple reaches the material, the yieldable' plunger I05 impacts the anvil. As this occurs there is a tendency for the frame of the tacker to recoil or rebound, thus materially reducing the intensity of the driving blow on the staple. By the present invention the recoil is materially and appreciably reduced by reason of the heavy laminated mass 14 situated above the driver in that the reacting force or recoil is transmitted to the driver through the blade, from the driver to the power spring 80, and ultipact applied by the plunger I05 on the anvil IIO the cover of the tacker characterized by the retained in the side walls 12 of the sheath 10, is

of strike the anvil H0, thus while the sheath 'becomes skin stressed, such stress is materially reduced and hence fracture of the sheath is precluded for the plunger of the driver strikes the sheath directly and the driver never strikes the steel anvil directly.

Pursuant to the tacking operation the control handle I I8 is still held depressed by the operator and on the removal of the hand pressure thereon, this handle revolves counterclockwise, (note arrow in Fig. 5) at which time lip I2I is yieldingly abutting the driver, being tipped slightly against the resisting action of arm I2'I of the spring I26, thus lugs I25 (Figs. 5 and 21) are away from the stop faces I24 of the arms In. By this construction it is possible for pawl I20 to move automatically into notch I30 when the control arm H9 is raised.

Where the tacker is idly operated or where it is used to tack into soft material, in the first instance there is no resisting medium offered to the ejection of the staples, and in the second instance the resistance is not great. In either of these instances the impact on the anvil on the part of the plunger is fairly great. But this intense impact is absorbed by the shock absorbing spring I01 (Fig. 5) which becomes compressed as head I06 of the plunger leaves its seat I02 and of course pursuant to the ejection of the staple, spring II instantly expands and the driver is automatically restored to its normal position in which instant the head of the plunger is again against seat I02.

By the'present invention it is apparent that where a relatively great, concentrated or localized mass is positioned over the driver the recoil of the frame of the tacker is materially reduced, and

consequently relatively less mass is required for the remaining parts of the tacker, therefore the latter merely comprises relatively light weight hollow members, for example, the sheath, case, and magazine, the components forming the frame of the tacker are merely of sheet metal stamped into channeled shaped forms, the sheath merely taking incidental internal stresses following driver impacts.

By reason of the fact that the frame of the tacker is hollow throughout and a concentrated mass is positioned above the driver, the weight of the tacker herein disclosed is appreciably light. Therefore in actual practice the tacker according to the invention reduces fatigue in the matter of operating and thus may be readily handled with a maximum of ease and convenience. Since also the internal stresses are merely transmitted to the sheath, the remaining parts of the cover and the magazine are not materially stressed, thus preventing these parts of the frame from getting out of relative alignmentthus precluding incidental buckling or breakage thereof, salient characteristics and advantages resulting by reason of the relatively heavy shock absorbing laminated mass over the driver which mass is relatively greater than the mass of the driver.

Where access is desired to the rail, the operator merely depresses manipulator I41 causing latch I45 to be tilted, thus removing the free ends or terminals IGI of the pintle or pin II from the aligned notches I62 of the wings I63 of the sides I3 of the magazine. Thereafter case and sheath thereof may be swung rearwardly (Fig. 2) until limited by the stop 51 and thus access is had to the staple rail. To close the cover, the latter is swung downwardly against the magazine whereby the free ends IGI of pintle I5I, ride on cam surfaces 200 of the wings I53 until reaching notches IE2 at which time spring I54 automatically shifts the roller I52 rearwardly and therefore the free ends I6I of the pin 'I5I become interlocked with the walls of notches I62. The tacker is now in its normally closed and locked relation and the swingable cover is prevented from accidental opening.

Thus it is apparent that a, relatively light weight tacker is provided wherein stabilizing means over the driver is utilized to absorb the frame recoil and wherein the acceleration of the driver is retarded by a reciprocable shock absorbing plunger cushioned by a relatively stiff Spring in axial alignment with a lighter power accelerator spring. These functional and structural features constitute important aspects and advantages of the invention in the matter of providing a relatively light weight tacker adapted to be conveniently operated and controlled. As a further aspect of the invention, the tacker herein specifically set out may be idly operated when empty of staples without causing fracture of the frame even though an intense impact is administered by the plunger of the driver to the abutment block or anvil H0 at the time the tacker is empty or even when staples are driven through soft or fluflfy material. These and other advantages are inherent in the herein disclosed tacker.

Furthermore it should be realized that with the tacker according to the invention, the frame thereof is of relatively thin sheet metal stock so that the overall width of the machine is only slightly greater than the width of the staple strip, hence permitting the tacker to be placed in narrow and ordinarily inaccessible-corners and also permitting staples to be driven therefrom even though the tacker be disposed contiguous to a wall or a corner and balanced and supported against transverse rocking when so disposed in difiicult positions for the operator.

By the present invention is it apparent that the relative light weight but stabilized staple tacker herein disclosed also embodies automatic staple follower action in the matter of closing or opening of the cover and providing complete inside accessibility to the staples in the staple raceway or guid'eway in the magazine at a time when the cover is swung rearwardly of the magazine at which time the latter may be conveniently loaded with staples even though the operator is in awkward positions, for example, such as on a step ladder, scaffold or the like. For reasons expounded in the foregoing detailed and complete disclosure, the successfully operatspaced sides, a'pin disposed transversely across said magazine and slidably sustained by said sides and having ends adapted to project laterally of said sides, a channeled shaped Saddle slidably guided transversely of said sides and having spaced arms secured to said ends for movably straddling said sides, and spring means including detent means for disconnectably interlocking with said pin to prevent displacement of said saddle transversely of said magazine.

2. In combination, a staple magazine having spaced sides, apin disposed transversely across said magazine and slidably sustained by said sides and having ends adapted to project laterally of said sides and including a reduced portion intermediate said sides and defining therewith spaced shoulders, a channeled shaped sad- I die slidably guided transversely of said sides and having spaced arms secured to said ends for movably straddling said sides, and spring means comprising spaced jaws including detent means adapted to be arranged within said reduced portion and cooperatingwith said shoulders for disconnectably interlocking with said pin to prevent displacement of said saddle transversely of said magazine.

3. In combination, a staple magazine having spaced sides, a pin disposed transversely across said magazine and slidably sustained by said sides and having ends adapted to project laterally of said sides, a channeled shaped saddle slidably guided transversely of said sides and having spaced upstanding arms secured to said ends for movably straddling said sides, and spring means disposed intermediate said sides and sustained by said pin and including detent means for disconnectably interlocking with said pin to prevent displacement of said saddle transversely of said means comprising spaced jaws including detent and having ends adapted to project laterally of said sides and including a contracted portion, a channeled shaped saddle slidably guided transversely of said sides and having spaced arms secured to said ends for movably straddling said sides, and loop spring means comprising jaws normally held widely spaced apart by said pin and including detent means disconnectably -engageable with said contracted'portion upon automatic movement of said jaws towards each other to prevent displacement of said saddle transversely of said magazine.

6. In combination, a staple magazine having spaced sides, a pin disposed transversely across said magazine and slidably sustained by said sides and having ends adapted to project laterally of said sides, a channeled shaped saddle slidably guided transversely of said sides and having spaced arms secured to said ends for movably straddling said sides, spring means comprising spaced jaws including detent means-for disconnectably interlocking with said pin to prevent displacement of said saddle transversely of said' magazine, a cover swingably mounted on said pin and adapted to be swung towards or away from said magazine to close or open the latter, and stop means carried by said saddle and cooperating with said magazine to limit the extent of movement of said cover rearwardly away from said magazine.

'7. In combination, a staple magazine having spaced sides, a pin disposed transversely across said magazine and slidably sustained by said sides and having ends adapted to project laterally of said sides and including a groove interposed between said sides, a channeled shaped saddle slidably guided transverselyof said sides and having spaced arms secured to said ends for movably straddling said sides and including a bottom seat interconnecting said arms, spring means sust'ained solely by said pin and including detent means for disconnectably interlocking with the walls of said groove to prevent displacement of said saddle transversely of said magazine, a cover swingably mounted on said pin and adapted to be swung towards'or away from said magazine to close or open the latter, and a lip extending from said saddle and cooperating with the rear of said cover to limit the extent of movement of the latter rearwardly away from said magazine.

8. In combination, a staple magazine having spaced sides, a pin disposed transversely across said magazine and slidably sustained by said sides and having ends adapted to project laterally of said sides, a channeled shaped saddle slidably guided transversely of said sides and having spaced arms secured to said ends for movably straddling said sides, an expandible and contractible loop spring comprising spaced arcuate jaws including detent means for disconnectably interlocking with said pin to prevent displacement of said saddle transversely of said magazine,

a cover swingably mounted on said pin and adapted to be swung towards or away from said magazine to close or open the latter, a staple supporting rail within said magazine, a follower slidably mounted on said rail, spring means inter connecting said follower and cover for shifting said follower rearwardly of said rail upon opening of said cover and for shifting said follower towards the front of said rail upon closing of said cover, driving means to expel a staple from said magazine, said follower having color indicator means, and one of said sides of said magazine having an opening for registering said indi- ,cator means.

9. As a new article of manufacture, a slidable saddle having upstanding arms, pin means connected to said arms and having a grooved portion, a support slidably carrying said pin means, and a spring clip comprising arcuate jaws encompassing said pin means and having detent means adapted to removably snap into said grooved portion to prevent displacement of said saddle relative to said support.

10. In a stapling machine, a staple magazine, a pin projecting laterally of and disposed transversely of said magazine and slidably sustained thereby, a stabilizing saddle having upstanding arms secured to said pin and' straddling said magazine, and disengageable locking means to prevent displacement of said saddle relative to said magazine comprising a spring clip mounted disengageable locking means to prevent displacement of said saddle transversely 0! said magazine comprising a spring clip mounted on said pin and including detent means and a grooved portion in said pin for removably interlocking with said detent means, said magazine embodying a bottom wall, and said saddle having a bottom wall substantially in horizontal alinement with the bottom wall of said magazine.

- STEPHEN A. CROSBY. 

